Hypodermic syringe



NOV. 6, 1951 LOCKHART 2,574,339

HYPODERMIC SYRINGE Filed Feb. 3, 1945 IN V EN TOR.

Patented Nov. 6, 1951 HYPODERMIC SYRINGE Marshall L. Lockhart, Detroit, Mich.

Application February 3, 1945, Serial No. 575,980

1 Claim.

This invention relates to hypodermic syringes and has particular reference to a novel and improved construction for an expendable, self-contained syringe assembly, including the needle and the medicament, which is adapted for a single use.

Syringes of this type known as syrettes are now commonly used by the military services. The principal object of the present invention is to make a syringe of this type which is cheaper in construction, more dependable in operation, and easier to use than devices of this kind heretofore available.

Other and further objects of the invention will be apparent from the following description and claims and will be understood by reference to the accompanying drawings, of which there is one sheet, which, by way of illustration, show a preferred embodiment and the principles thereof and what I now consider to be the best mode in which I have contemplated applying those principles. Other embodiments of the invention embracing the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claim.

In the drawings:

Fig. 1 is a side elevational view of a device embodying the invention;

Fig. 2 is an enlarged, longitudinal sectional view thereof with certain parts shown in elevation;

Figs. 3 and 4 are sectional views taken generally in planes along the lines 3-3 and 4-4, respectively, of Fig. 2; and

Fig. 5 is a fragmentary sectional view of the the holder taken along the line 5-5 of Fig. 2.

The device, as clearly illustrated in Figs. 1 and 2, consists in general of a holder l0, an ampule l2, a double-ended hollow needle I 4, and a cap Hi. The holder It! as illustrated comprises an integral molded hollow transparent plastic body member having the needle I4 molded or secured therein with one end l8 of the needle projecting from a boss 20 on the holder. The holder is internally provided with a hollow post or stem 22 (of which the boss forms a part) through and beyond which the other end 24 of the needle extends. The end 26 of the post 22 forms an abutment for cooperation with the stopper 28 of the ampule 12 upon movement thereof relative to the holder ID for expressing medicament through the needle l4 and from the end I8 tbereoi. The holder II) at its open end may be provided with a cylindrical bearing surface 30.

The ampule l2, as illustrated, comprises an integral molded plastic tubular member closed at one end thereof and having an internal bore 32 which is adapted to be filled with a measured quantit of medicament. The bore is closed by the stopper 28 which is conveniently formed of flexible, resilient material, such as a wax-impregnated rubber. This is adapted to seal the bore 32 for holding the medicament therein and also to slide toward the closed end of the bore 32 so as to act as a piston for displacing medicament from the bore 32 in the manner hereinafter explained.

After manufacture the parts are arranged substantially as illustrated in Fig. 2, with one end of the ampule telescopically disposed in the bore of the holder I 0. If such a surface as 33 is employed it will slidably support and guide the ampule. By telescoping movement between the holder l0 and the ampule I2 the stopper 28 will move against the pointed end 24 of the needle and will cause the needle to puncture the transverse Wall 34 so as to afford communication of the interior of the needle with the medicament in the bore 32. The cap I6 is frictionally fitted on the boss 20 and is removed therefrom before i the device is to be used. The end l8 of the needle may be injected into the tissue into which the medicament is to be expressed before the telescoping movement of the holder l 0 and ampule l2.

As soon as the diaphragm 34 of the stopper 28 contacts the end 26 of the post 22 during the telescoping movement of the holder Ill and ampule I 2, the stopper 28 will come to rest relative to the holder l0. Upon further movement of the ampule l2 relative to the holder In, the stopper 28 will function as a piston to displace the fluid from the bore 32 through the needle H. The space between the post 22 and the outer wall of the holder I0 is annular and designed to accommodate the ampule l2 in its fully telescoped position relative to the holder ID as illustrated in dotted lines in Fig. 2.

The outer end of the ampule l2 may be formed to provide wings 36. Accordingly with the parts arranged as illustrated in Fig. 2, the ampule 12 may be rotated relative to the holder ill so as to break any seal therebetween. Such a seal may be provided by a layer of wax 38.

In order to properly guide the ampule l2 relative to the holder l0 during the assembly of the device, the open end of the ampule I2 may be provided with a pair of laterally extending lugs 40. These are adapted to be located in recesses 42 formed in the interior cylindrical wall of the holder ID, as illustrated in Figs. 3 and 5. With a view to initiating operative cooperation of the parts, the open end of the holder 10 may also be provided with a cam track or ledge 44 facing toward the closed end of the holder ID. The track is arranged so that as the ampule I2 is rotated about its axis relative to the holder 10, the lugs 40 cooperating with the rises 46 in the cam track will cause the ampule l2 to telescope relative to the holder 13 so as to help break the seal between the holder l and the ampule 12. the end 24 of the needle into the diaphragm-34 of the stopper 28, and engagement of such stopper with post 22.

The holder I0 may be providedwithlears 50:

to facilitate grasping the holder I0 between the fingers While pressure is exerted by the thumb against the outer end of the ampule 2 for telescoping the'same into the holder Ill.

While I have illustrated and described a preferred embodiment of my invention, it is understood that this is capable of modification and.

Iltherefore do not Wish to be limitedto the precise details set forth but desire to avail myself of suchchanges and alterations which fall within thepurview of the following claim.

Iclaim; A hypodermic syringe-including a tubular body having one open end, awall for the opposite endofsaid body, a post extending from the inner face of .said wall, within said body,'towards the open end thereof and spaced from the'inner This will result in initial penetration of"- face of said body, said body, end wall and post being all formed of a plastic material and integral with each other, a bored needle extending transversely of said end wall with the material of the latter intimately engaging and enveloping its adjacent faces, said needle having one of its ends extending beyond said wall and body, its opposite end extending longitudinally of and within said postto a point beyond the latter and short of the edge defining the open end of the tubular body, a stoppered ampule insertable through the open end of said tubular body to bring said stopper adjacent the latter end of 'saidtneedle and cooperating camming means formingparts of said body and ampule to cause the latter end of the needle to penetrate said stopper-and forthe 1 post to engage the latter.

MARSHALL L. LOCKHART.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,142,682 Dickinson June 8, 1915 1,848,711 Hall Mar. 8, 1932 1,860,898 Meyer May 31, 1932 2,233,554 Pletcher Mar. 4, 1941 2,290,348 Moule July 21, 1942 FOREIGN PATENTS Number Country Date 546,444 Great Britain July 14, 1942 

